remember me how to delete python2.7 in Linux

[DeaD_EyE]

I'm using pyenv together with xonsh and some other libraries, which also requires the shared libs and header files.
The installation was not easy. The text above must added to your .bash_profile in your home directory.

Just edit the file:

nano ./.bash_profile

then add this and save the file.
Nano: CTRL+X y Enter

export PYENV_ROOT="$HOME/.pyenv"
export PATH="$PYENV_ROOT/bin:$PATH"
eval "$(pyenv init -)"

Then close the old and open a new terminal.
Look if the environment variables have been set.

echo $PATH
echo $PYENV_ROOT

In $PATH must a path like: /home/deadeye/.pyenv/bin
Path of PYENV_ROOT: /home/deadeye/.pyenv

The path was evaluated from the shell before it was added to the environment.

Then don't forget, that you need build tools.

For debian source 1 [source 2]

apt install build-essential
apt-get install libssl-dev zlib1g-dev libncurses5-dev libncursesw5-dev libreadline-dev libsqlite3-dev 
apt-get install libgdbm-dev libdb5.3-dev libbz2-dev libexpat1-dev liblzma-dev tk-dev

Download, Build, Install Python 3.7.0

env PYTHON_CONFIGURE_OPTS="--enable-shared"
# i used this for nuitka i guess
pyenv install 3.7.0

If there is an update of python, you can change the current working cd ~/.pyenv, then git pull.
Then install the newest version.